A. Field of the Invention
This invention relates to a new and improved assembly for holding a tool bit used to machine an out-of-round work piece. In particular the invention relates to a slidable assembly used in connection with a clamshell lathe for machining a work piece.
B. Description of the Related Art
My previous U.S. Pat. No. 4,739,685 on a clamshell lathe assembly teaches how to machine a pipe and provide a bevel cut using a clamshell lathe. The major benefit of the '685 patent is that it allows one to easily attach and detach the lathe from the work piece to be machined. A tool bit mounted in a tool slide affixed to the rotatable ring of the clamshell lathe then orbits the pipe and machines said pipe.
A problem arises however when the work piece is out-of-round. Prior lathe assemblies are designed for circular work pieces. Out-of-round work pieces present a special challenge because the prior art tool bits tend to make an uneven cut of the out-of-round work piece. Specifically, if the tool bit does not follow the outside surface of the work piece, the bevel length of the cut changes at locations where the work piece is out-of-round. Thus, a need exits to provide a tool bit slide that can follow the outside diameters of the out-of-round work piece.